It goes without saying that electric vehicles differ vastly from gasoline-powered cars. One such quirk is that you’re unlikely to see any orange cables under the hood of your gas car. Meanwhile, an EV will be chock full of them. Whether the cables have orange insulation or are covered by orange conduits, that indicates upward of 400 volts could be traveling through them. While 400 volts is more than enough to kill a person, EV technology may eventually graduate to a whopping 1,000 volts flowing through cables. In fact, Volvo recently released its first EV with 800 volts.
So why orange? Obviously, orange is an attention-getting, high-visibility hue. But the official mandate comes from 2017’s Federal Motor Vehicle Safety Standard No. 305, which “requires orange color outer coverings for cables of high voltage sources that are located outside electrical protection barriers.” Some sources believe that decision was influenced by the National Electric Code, which calls for labeling high-voltage (also called high-tension) cables in orange — not just in vehicles, but also buildings and workplace environments like a factory floor.
The orange cladding of high-voltage EV cables serves as a warning to folks like mechanics and emergency responders not to handle them without special training and safety equipment. Note that not only high-tension cables bear the color orange. Other high-voltage EV components like the DC/DC converter, charging port, and even the air conditioning compressor may also be clad in orange for safety.
Emergency responders: Beware orange cables
Under normal circumstances, the orange insulation or sheathing that covers high-voltage EV cables is sufficient to prevent humans or animals from being harmed by accidental contact. That said, it’s still good practice to give them a wide berth when servicing or cleaning your electric vehicle. However, if the high-voltage cables become damaged, such as during a collision, they shouldn’t be handled at all. That’s because the insulation can get cut or nicked, exposing the high-voltage metallic wiring inside.
So what should emergency responders do when encountering a situation involving an EV? Vehicle manufacturers provide specific instructions in the form of emergency response guides. But generally speaking, there’s a well-marked first responder loop that’s safe for emergency personnel to either cut or dislodge by firmly pulling an obvious strap. For example, the Tesla Model 3 has a first responder loop in the front trunk. It both disables the entire high-voltage system and deactivates the airbags. If a Model 3’s frunk can’t be accessed, there’s a secondary first responser loop under the rear passenger-side trim panel that can be severed by breaking the glass, then cutting through the metal with emergency equipment.
As more EVs join their fossil-fuel counterparts on America’s highways and byways, firefighters, police officers, and EMTs are well advised to acclimate themselves with the correct procedure to disarm different models’ high-voltage systems. That definitely includes Tesla, a brand involved in a disproportionately high number of crashes.